Microsoft has given a name to its Windows Messenger successor: Office Communicator 2005. The new communications client, formerly known by its code-name Istanbul, integrates IM, voice, video, telephony and Web conferencing capabilities into a single interface and makes them accessible in Microsoft's Office applications.

Communicator serves as the preferred client for Office Live Communications Server (LCS) 2005, which streamlines business communication and is the core of Microsoft's real-time collaboration vision. With Communicator, users have access to presence features that rout incoming messages based on a schedule, or offer additional availability data such as the next available meeting.

"The relationship between Istanbul and LCS is similar to that between Exchange and Outlook," a Microsoft spokesperson told BetaNews. "LCS is the enterprise grade server and Istanbul is the enterprise client software."

Because Communicator integrates with Office System applications, users can directly initiate voice, video or text communication directly from Microsoft Outlook or SharePoint.

"Users now can view rich presence information for colleagues, partners and customers; select the most efficient mode of communication, whether it's IM, a phone call, a Web conference or e-mail; and instantly share ideas and information," said Jeff Raikes, group vice president of the Information Worker Group at Microsoft.

To break down the barrier between businesses using different IM networks, Microsoft has developed a public instant messaging connectivity (PIC) add-on to LCS 2005. The pack, which is offered on a paid subscription basis, connects MSN, AOL and Yahoo IM networks from within Istanbul.

The PIC will require a service pack for LCS 2005, also announced Tuesday. Changes in the service pack include added federation tools to connect multiple organizations using LCS, along with improved instant messaging spam, or spim, blocking.

"With the reach that PIC and enhanced federation provide, enterprise IM becomes a first-class business tool -- as useful and ubiquitous as e-mail," said Gurdeep Singh Pall, corporate vice president of the Live Communications Team at Microsoft.

Office Communicator 2005 is expected to be released to manufacturing within 90 days. The LCS 2005 service pack will be available as a free download starting next month.

"With LCS and Communicator, organizations have a safe, easy way to IM and share presence information with colleagues, partners and customers," Pall said.